I made it as a cone for the top and a low cylinder for the base. Go and see the screenshots HERE.

Now, the 'left' side is OK (shots 1 to 3), nice and rounded, but the 'right' side (shots 4 to 6) is very, very strange. It's angular instead, and you can walk through bits of it. In fact, it's as if on that side the real edge is invisible and solid where as you can see the not-real edge but walk through it.

What is causing this problem?

(Does any of that make sense?)

--RelFexive-->
All I want is a warm bed, a kind word and unlimited power